﻿namespace ConsoleApp1
{
    internal class Program
    {
        static void Main()
        {
            string s = "";
            double a = 0;
            double b = 0;
            string op = "";

            Console.Clear();

            Console.Write("Please enter the first number:");
            s = Console.ReadLine();
            a=Double.Parse(s);

            Console.Write("Please enter the second number:");
            s = Console.ReadLine();
            b = Double.Parse(s);

            Console.Write("Please enter the operation:");
            s = Console.ReadLine();
            op=s;

            if (op == "+")
            {
                Console.WriteLine($"a+b={a + b}");
            }

            else if (op == "-")
            {
                Console.WriteLine($"a-b={a - b}");
            }

            else if (op == "*")
            {
                Console.WriteLine($"a*b={a * b}");
            }

            else if (op == "/")
            {
                Console.WriteLine($"a/b={a / b}");
            }

            else
            {
                Console.WriteLine($"Wrong");
            }

            Console.Write("Please enter the next step(1:continue;else:end):");

            string ss=Console.ReadLine();

            if (ss == "1")
            {
                Main();
            }
            else 
            {
                return;
            }
        }
    }
}
